Oh hell... sorry for the error Matt. I messed up the order of operations when aggregating some of the constants in the formula from what I worked out in Excel versus what I gave to you. The correct constant is 112.5, not 5.555555 (112.5 is 25*4.5, whereas I gave you 25/4.5).

So the correct formula is

Page score = 70 + 30 * [1-1/e^((x-5.5)*y/112.5)]

That should give the exact results of my examples.

To explain the constants:

5.5 in the formula is used to define a neutral vote (as Bob correctly explained). Thus a ten gets treated as a 4.5, a nine as a 3.5, a six as a 0.5, and a one as a -4.5 for example. This is why an eight counts about half as much to the score as a ten (actually 55% as much since 2.5/4.5 = 55%). A six counts 11% as much (0.5/4.5). And any vote under 5.5 is negative and starts lowering the score.

The other constant, 112.5 being the correct one (not 5.555555 anymore) is what affects how quickly scores increase. 112.5 is 25 * 4.5 and has the effect of increasing a page score by 4% of the remaining amount from the previous score towards the eventual goal of 100 for each 10 vote received (25 is 4% of 100 and 4.5 is the value of a 10). To increase scores faster... like 5% for each 10, use 20 * 4.5 = 90. For smaller changes with each vote the constant is increased (225 will increase scores 2% for each 10 and takes twice as many votes as the current formula). In picking a constant I tried to balance between the score not changing too rapidly if a bunch of 10s were given, but also changing enough to be noticed if only a few 7s and 8s were received.

This 112.5 constant can basically be anything depending on how much you want to change the score, but the above shows how to determine the value if you already have a desire in terms of what magnitude a single vote should result in.

Last edited by mrchad9 on Mon Jan 14, 2013 9:11 pm, edited 1 time in total.

A simpler version of what Chad is proposing was discussed in 2011. Whether it works better or worse, I dunno.

chugach mtn boy wrote:

Alpinist wrote:Hooboy. Are we really opening this can of worms again? The voting system has been discussed ad nauseum in the past. I was a big proponent of changing it when SP2 was first launched but it may be too late now since all of the current votes are based on a binary scale (10 or nothing).

The formula that should have been implemented is based on a weighted average 10 point scale.

In this example, only 3 people voted. Simply extend the formula for any number of people.

This would yield the results that people are expecting to see. Scores would be based on a 10 point grading scale similar to the way schools grade. If an object had a score of 88 and you voted 9, the score would always increase slightly based on your Power Ranking. Similarly, if you voted 8 on that object, the Score would always decrease. There are no quirky exceptions. The calculation would always work as expected.

The weighted average method gives members with a higher Power Ranking a greater ability to influence the Score.

This is a nice starting point, but it would mean that most objects on SP would be rated 100. If one person voted 10/10 and nobody else voted, that object would go straight to 100, same as an item with 96 votes of 10, and ahead of an item with 95 10 votes and one 9 vote.

The one thing that is good about the current system, and that ought to be preserved when it is reformed, is the concept of a "par" score set well below 100. Right now, par is 85, and you need some 10 votes to progress above that; you need a lot of 10 votes to get into the 90s.

You could keep par at 85 and create a built-in gravity that pulls items toward par unless gravity is overcome by votes. Using Alpinist's example, it would work mathematically like this (the example also tweaks one other aspect of Alpinist's formula so as to produce scores on a scale of 100, which I believe was his intent):

With the above example, if 3 people with power of 100 each vote, respectively, 10, 9, and 10, you end up with a score of 87.69. If they all vote 10, the score is 88.46. If they vote 10,9, 10 but one of the "10" voters is Dow and has power of 1000, the score goes to 92.72 (even though one of the 3 votes was a "9").

You can increase the "par gravity" by increasing the automatic add-on to the numerator and denominator. The system would probably work best with somewhat stronger gravity than in the above example--maybe I'd go with +850,000 in the numerator and +10,000 in the denominator. But 9 would still be a positive vote in such a system.

If you want 8's and 7's to be (marginally) positive votes, par needs to be lowered to less than 70. This is easily done. For example, the automatic add-on in the numerator could be 600,000 and the automatic add-on in the denominator 10,000, and, mission accomplished: 7-10 would be positive votes to varying degrees, at least initially; 6 would be neutral; and 1-5 would be negative. Note, however, that a 7 vote on an item that had already progressed to a high score (such as 90) would have a marginally downward effect, although much less than it currently has. [Edited for clarity]

That formula does not accomplish what I propose. The goal of the formula I proposed was to make 6-10 ALWAYS positive votes. I believe that any other method will gravitate towards everyone using 10/10, or at least some negative connotations being associated with lower than 10 votes. If 6 is a positive vote 100% of the time, and every time you vote it you immediately see page scores increase, then there should be less resistance to most people using them.

Not sure. But based on Matt's comments in another thread, I was inclined to believe dropping in a new formula was less work for Matt than changing to a new system... even if two votes seems simpler than a 10 vote system on the surface.

It looks promising to me! Which is great news considering how much this voting system has bothered so many of us for so long. I'd nearly lost hope. I hope more members start voting in the future now that every page isn't automatically between 87 and 90%.

While I don't pay too much attention to page scores and rankings due to the current setup, I put a lot of work into pages and I admit it pleases me when 40+ people make the small effort to acknowledge it by voting on one.

Chad has devised something quite clever here. I also like his add-on idea, one page up, of making very low votes especially powerful--if two or three people really ding a page, it's usually because it has some colossal flaw that knowledgeable people can spot, and this should outweigh the the mindless 10/10s.

I would also favor incorporating a power points element so that major contributors have more say than casual drop-ins.

All I can say is with the current voting system it seems absurd that one 9/10 vote can have a major impact on a pic or page with, say, 20 10/10 votes! It's like if you get a less than 10/10 vote the voter appears to be deliberately undermining all the other votes. And one 1/10 vote....forget about it!

Last edited by Noondueler on Tue Jan 15, 2013 7:42 am, edited 1 time in total.